1. Field of the Invention
This invention relates generally to fluid control valves, and more particularly to a fluid control valve having a spring biased shuttle plunger member which opens or closes fluid flow between an upstream and downstream side of the valve body responsive to a fluid pressure greater than the spring force and any differential pressure between the upstream and downstream side to prevent fluid from being supplied at a pressure higher than a desired operating pressure and prevent high dynamic differential pressures, such as a “water hammer” or explosive pressure.
2. Background Art
Fluid control valves of the on-off type that allow full fluid flow or completely shut off the fluid flow are well known in the art and are available in a wide range of various designs, sizes, pressure capabilities, and modes of operation. Such conventional valves are often identified by the configuration of the main valve components, such as the part that which opens and closes the fluid passage, and are commonly referred to as gate valves, butterfly valves, cock valves, globe valves, ball valves, poppet valves, shuttle valves and stem valves. As the working fluid pressure increases, the selection of suitable on-off valves decreases due to the difficulties in achieving fluid sealing and in operating the moving valve parts.
Typically, such valves capable of handling relatively high fluid differential pressures utilize a hardened valve stem, valve needle or valve poppet, usually of circular cross section, which is raised or lowered against a circular fluid passage commonly positioned at the center of a replaceable valve seat constructed of hardened metals. Conventional high-pressure on-off valves require a rotating motion, either manually or automatically, for raising or lowering a valve stem or valve needle. In many applications, such rotary motion is too slow and does not provide the required instant on-off action. In such case, the valve stem or valve needle must slide within the valve cavity to open or close the valve port.
Typically, the end of the valve stem which is exposed to the atmosphere is in contact with a source of force that imparts the sliding movement to the valve stem. Such force can be supplied by a human hand or by automatic or powered devices, such as with compressed air, pressurized hydraulic fluid, electricity or the like. Conventional solenoids, pneumatic or hydraulic actuators are also used to supply linear force to move the valve stem.
Check valves are also well-known and widely used in fluid systems of various types to permit fluid flow in one direction therethrough while preventing fluid flow in the opposite direction. Such check valves have a variety of different forms, principally ball check valves in which a spherical ball is held by a spring adjacent a seat until opened by fluid pressure overcoming the spring bias, and check valves having generally conical valve members operating in a similar manner as the ball check valve.
Dashner, U.S. Pat. No. 4,172,465 discloses a check valve having a semi-spherical valve member movable longitudinally in a generally tubular housing between a closed position engaging a conical valve seat and an open position spaced longitudinally therefrom, the valve member being slidably mounted for such movement on a longitudinally extending support element. The opening in the valve member which receives the support therein has a diameter significantly greater than the diameter of the support element whereby the valve member is pivotal thereon so as to seat properly on the valve seat. The center of the semi-spherical valve member is longitudinally spaced in one direction from the effective center of support thereof at the closed position of the valve member, and is longitudinally spaced in the opposite direction from the effective center of the valve member at the open position of the valve. The valve housing is specially formed to provide a flow path around the valve member which corresponds generally in area to the valve inlet and outlet openings to reduce the pressure loss of the fluid passing through the valve.
Muruyama et al, U.S. Pat. No. 5,271,430 discloses A flow rate control valve device for controlling and then supplying fluid under pressure to an actuator such as an hydraulic cylinder or the like which includes a valve body having a drain port kept at a low pressure and a main spool slidably mounted in the valve body to connect or disconnect the drain port with a pressure chamber. Notch grooves are formed on an outer peripheral surface of the main spool. A spring is interposed between the valve body and the main spool to urge the spool to a valve body seat. A pushing device is provided for pushing the main spool against the resilient force of the spring. A plate member is provided on the main spool in the drain port for causing pressurized flow through the notch grooves to flow first in a substantially radial direction of the main spool and subsequently into the drain port so part of the pressurized fluid impinges on the plate member for exerting a force urging the main spool in the direction disengaging the spool from the seat against a force of the spring and a flow force acting between the spool and the seat for at least canceling the flow force.
Tavor, U.S. Pat. No. 6,220,272 discloses in-line control valves which include a piston-type valve assembly and a plurality of control chambers controlled via one or more controls ports to provide a normally-open valve that may be closed by controlling the fluid pressure applied to the control port, or a normally-closed valve which may be opened by controlling the fluid pressure applied to the control port. Also described are valves which have a balanced construction and include relatively small actuators for opening and closing the valve.
Haeberer et al, U.S. Pat. No. 6,244,253 discloses a pressure control valve for a fuel injection apparatus for internal combustion engines, including a housing with a high-pressure connection and a return connection and including a cup-shaped piston, which is disposed in a housing bore, can be moved axially between a valve seat oriented toward the high-pressure connection and a stop oriented toward the return connection, counter to the spring force of a spring acting in the direction of the valve seat, and has at least one through opening that connects the inside of the cup-shaped piston to the housing bore, and is characterized in that at least one throttle element is disposed upstream and/or downstream of the valve seat in the flow direction of the fuel.
Kussel, U.S. Pat. No. 6,263,913 discloses a hydraulic multiway valve having a control piston, which is displaceable against the force of a spring by the plunger of a magnet from its closing position to its opening position. In the closing position, a pressure chamber with a pump connection is closed toward a consumer chamber, and the consumer chamber with a consumer is opened toward a return flow chamber and a reservoir connection. In the opening position, the consumer chamber is closed toward the return flow chamber. The consumer chamber and the return flow chamber are arranged at the opposite ends of the main piston, namely the consumer chamber on the side facing the magnet, and the return flow chamber on the side facing away therefrom. A central channel extends through the main piston and interconnects the consumer chamber and the return flow chamber. A magnet plunger acts upon a plunger piston, which is displaceable in the valve housing in coaxial relationship with the main piston, and which comprises a seat end facing the main piston, through which it closes the central channel, when it contacts the main piston.
The present invention is distinguished over the prior art in general, and these patents in particular by a fluid control valve having a spring biased plunger or shuttle member which opens or closes fluid flow through a plurality of radially spaced apart fluid passageways disposed between an upstream chamber and downstream chamber in the valve body responsive to a fluid pressure greater than the spring force and any differential pressure between the upstream and downstream chambers to prevent fluid from being supplied at a pressure higher than a desired operating pressure and prevent high dynamic differential pressures, such as a “water hammer” or explosive pressure. Alternatively, in a normally closed embodiment, pilot fluid at a pressure greater than the spring force and any differential pressure in the upstream chamber is utilized to open the valve.